Terrorism: Commentary on Security Documents is a series that provides primary source documents and expert commentary on various topics relating to the worldwide effort to combat terrorism. Among the documents collected are transcripts of Congressional testimony, reports by such federal government bodies as the Congressional Research Service (CRS) and the Government Accountability Office (GAO), United Nations Security Council resolutions, reports and investigations by the United Nations Secretary-General and other dedicated UN bodies, and case law from the U.S. and around the globe covering issues related to terrorism. Most volumes focus on a single theme, and inside each volume the documents usually appear within topic-based categories. The series also includes a subject index and other indices that guide the user through this complex area of the law.Volume 133, The Drone Wars of the 21st Century: Costs and Benefits, examines the complex issues raised by the use of unmanned aerial vehicles, or drones, in lieu of more conventional military capabilities. Professor Douglas C. Lovelace, Jr., who provides the introductory commentary for this volume, has selected ten documents that provide invaluable insights into the various aspects of this topic. These documents examine such issues as the legality, constitutionality, and ethics of the current use of drones by the United States, including the targeting and killing of U.S. citizens abroad. The long-term efficacy of U.S. reliance on drone usage as a counterterrorism tactic is also considered, as are the challenges involved for the United States in limiting the proliferation of drone technology through export controls and diplomatic efforts.